Heating hydrocarbon fluids



April 8, 1941. .1. H. RlcKERMAN 2.237.502

HEATING HYDROCARBON FLUIDSI Filed Aug. 5, 1939 A; 5 v INVENTOR ,so A 12? E; .rou/v HERMA/v Mmmm/v B BY ATTORNEY Patented Apr. 8, 1941 UNITED STATES r Fri@- HEATING HYDRCARBN FLUIDS John Herman Itickerman, River Edge, N. J., as-

signor to Gasoline Products Company, Inc., Jersey City, N. J., a corporation of Delaware Application August 5, 1939, Serial No. 288,539

8 Claims.

rality of hydrocarbon fluid streams passing through the heater tubes in the heating apparatus.

Where it is desired to heat large volumes of hydrocarbon fluids without increasing the size of the heater tubes, it is undesirable to heat such large volumes of fluid in heater tubes as a single stream for the reason that excessive pressure drop is encountered. Where large volumes of oil or hydrocarbon fluids are to be heated to conversion temperature, it is advantageous to subdivide the hydrocarbon fluid into a plurality of streams and pass such streams in parallel flow through a heating apparatus to provide uniform heating for the separate streams. If usual fourhole headers are used for heating two streams of oil in parallel, there is mixing of the two streams in the headers and segregation occurs between light and heavy phases in the streams, so that on leaving the headerone tube may be lled with 1iquid and another tube lled with vapor and unequal heating results.

According to my invention the heater tubes in a radiant heating section are arranged to have the ends of alternate heater tubes offset with respect to the ends of the rest of the heater tubes and jump-over headers are used between alternate tubes. In my Vpreferred construction the jump-over headers for a row of heater tubes are all arranged on one side of the heater tubes in that row. In this way the heater tubes in a single row and the rows of heater tubes in a double row are spaced closer together than would be possible with standard constructions and the plural streams of hydrocarbon fluid passing through the heater `tubes pass through substantially the same sections in the furnace and receive substantially the same amounts of heat in passing through the heating apparatus.

In a specific form of my invention the heating apparatus. includes two radiant heating sections and a common overhead convection heating sec tion receiving hot products of combustion from both radiant heating sections. The convection heating section is preferably provided with heater tubes to preheat streams of hydrocarbon fluid, such as gas oil, before passing them to the radiant heating sections or zones. In this form ofmy invention the heater tubes in one radiant heating section are preferably arranged in a single row adjacent the roof and side wall thereof and the two streams of hydrocarbon fluid are heated in passing through the single row of heater tubes.

The other radiant heating section is preferably l provided with a double row of heater tubes arranged adjacent the roof and side wall thereof and the two heated streams of hydrocarbon fluid from the first radiant heating section are passed as separate streams through the exposed rows of heater tubes in the second mentioned radiant heating section and are then passed through the shielded rows of heater tubes in the second mentioned radiant heating section. Fuel'is burned in the radiant heating zones or hot combustion gases are supplied to the zones to provide radiant heat for heating the hydrocarbon fluid in the heater tubes. Floor tubes may be used `in both radiant heating sections, if desired.

In the double rows of heater tubes in the second radiant heating section `the heater tubes in each row are arranged to have the ends of alternate tubes in staggered relation with the ends of the remaining tubes in the row and jump-over headers are used to connect alternate tubes. All of the jump-over headers for the exposed rows of heater tubes are arranged on one side of the heater tubes and all of the jump-over headers for the shielded rows of heater tubes are arranged on the other side of the shielded rows of heater tubes so that the heater tubes in the rows of heater tubes are arranged closer together without interference by the jump-over headers. According to my invention, heating apparatus may be used in which the radiantheating section or sections contain only single rows of heater tubes or only double rows of heater tubes.

In the drawing,

Fig. 1 represents a vertical transverse cross section'taken through a heating apparatus constructed to embody my invention;

Fig. 2 represents a partial horizontal cross section taken on line 2-2 of Fig. 1 to show the arrangement of the heater tubes in a portion of the single row of heatertubes in-one radiant heating section;

Fig. 3 represents a partial vertical cross section taken on line 3--3 of Fig. 2 showing the arrangement of the jump-over headers;

i Fig. 4 represents a partial vertical cross section taken on line 4-4 of Fig. 2;

, Fig. 5 represents a partial, enlarged top plan view of the double row of heater tubes in the second radiant heating section and taken substantially along line E--J in Fig. 1 with the header box omitted;

Fig. 6 represents a reduced end View showing the arrangement of the jump-over headers for the double row of heater tubes; and,

Fig. 7 represents a diagrammatic showing of the flow of the plurality of streams through a portion of the double row of heater tubes in the second radiant heating section.

Referring now to the drawing the reference character IIJ designates a heating apparatus or furnace provided with radiant heating sections I2 and I4 and a common overhead convection heating section I6 for receiving hot products of combustion from the radiant heating sections I2 and I4. The radiant heating section I2 is provided with burners or the like 25 which are diagrammatically shown in full lines and which are arranged along or extend through one end wall 2| of the furnace. Other burners 0r the like shown in dotted lines at 22 represent burners in the other end wall (not shown) of radiant heating section I2.

Radiant heating section M is provided with burners or the like diagrammatically shown at 24 which are arranged in the end Wall 2| oi the furnace or heating apparatus. The burners or the like 26 shown in dotted lines represent burners which are arranged in the opposite end wall (not shown) of the radiant heating section I4. By means of the burners or openings in the furnace wall, fuel is burned in or hot gases of combustion are introduced into the radiant heating sections to provide radiant heat for heating the heater tubes and the hydrocarbon fluid streams passing therethrough. Other means of generating radiant heat may be used.

While no bridge wall has been shown in Fig. l for separating the radiant heating sections I2 and I4, if desired, a suitable bridge wall may be included.

The convection heating section I6 is provided with two banks of heater tubes 30 and 32 for preferably prehe-ating separate streams of hydrocarbon fluid. One stream passing through line 34 and designated stream A is passed through bank 30 of heater tubes in the convection heating section I6. Another stream passing through line 3S and indicated stream B is passed through the other bank 32 of heater tubes in the convection heating section. The separate streams A and B are passed through alternate heater tubes in the single row of roof tubes 38 and side wall tubes lt and during passage through these heater tubes the streams are maintained separate and in parallel flow. If desired, oor tubes may also be used in the radiant heating section I2.

The passage of the streams A and B through rows 38 and 4B in section I2 will now be more specifically described. Stream A preheated after passing through the bank of heater tubes 3@ in the convection heating section is passed through line 42 and preferably through the iirst heater tube 44 in row 38 and then through jump-over header 46 at one end of the heating apparatus to an alternate heater tube 48. After passing through heater tube i8 the stream A is passed through jump-over header i) at the opposite end of the heating apparatus and through heater tube 52. Stream A continues through alternate tubes and jump-over headers in its flow through rows 38 and 40 of heater tubes. It will be seen that jump-over header 4S yis shown in dotted lines. while jump-over header 5U- is shown in full lines-so as to represent jump-over headers at opposite ends of the furnace and to distinguish from the headers at opposite ends of the furnace or heating apparatus. The arrangement of the heater tubes and jump-over headers will be presently described. The jump-over headers have been diagramniatically shown as the actual construction thereof is within the skill of the art.

The stream designated B after being preheated by passing through the bank 32 of heater tubes in the convection heating section is passed through line 56 to the second heater tube 58 in row 33 and through jump-over header 69 shown in dotted lines and passed into the heater tube 62 arranged between heater tubes 48 and 52. The stream B after passing through heater tube 62 passes through jump-over header iid to heater tube 66 arranged adjacent heater tube 52. From the drawing it will be seen that the separate streams A and B are passed through alternate tubes in the single row of heater tubes and the stream-s continue their passage as separate streams through alternate tubes in the single rows 33 and it of heater tubes in, the radiant heating `section i2 by means of jump-over headers.

In radiant heating zone I2, the rows 38 and i of heater tubes and the hydrocarbon uid passing therethrough are heated by radiant heat to raise the temperature of the hydrocarbon fluid streams to conversion temperature before being passed to the second radiant heating Zone Ill. Streams A and B are then passed through lines 'i9 and 'l2 respectively and passed as separate streams through double rows of heater tubes heated by radiant heat generated in the second radiant heating section Ifl as will be hereinafter described in greater detail.

Referring now to the arrangement of the heater tubes in the single rows 38 and 4i] of tubes shown in radiant heating section I2, attention is directed to Figures l to 4 inclusive. Alternate heater tubes such as heater tubes M, 48 and 52 as shown in Fig. 2, have their ends offset with respect to the other heater tubes in the row 3B such as tubes 58, 62 and 38. In other Words the ends of the heater tubes in each row are in staggered relation and the ends of alternate tubes are in the same vertical plane where the heater tubes are arranged horizontally. The heater tubes in the rows 38 and il!) are of the same length but due to the oiset relationship, the ends of adjacent tubes lie in different planes. Ends of 'alternate tubes are connected by jump-over headers such as ISS, 50, 6i] and Ell, as shown in Fig. 2 of the drawing. Stream A passing through tubes 4t, cl3, 52, etc., passes through headers 46, 50, etc., while streain B passing through tubes 53, 6?., 66, etc., passes through headers 60, 64, etc. The jump-over headers are arranged in header boXes i3.

Because the ends ol adjacent tubes lie in different planes, the jump-over headers connecting alternate tubes and arranged in one header box do not interfere with other jump-over headers connecting adjacent tubes, that is, the jumpover headers connecting the pairs of tubes such as jump-over headers t6 and 0 are laterally displaced with respect to each other and the head- Tier @l5 is positioned adjacent one side wall I4 of the header box 'I3 while the other jump-over header Si) is arranged adjacent the other side wall 'I5 of the header box 13. With this arrangement of heater tubes, the jump-over headers for the entire row of heater tubes are preferably placed on one side of the row of heater tubes. As shown in Figs. 1 to 4 all of the jumpover headers of the single row 38 0f roof tubes extend above the plane of the row of heater tubes. The jump-Over headers for row 48 also all extend from one side of the row of heater tubes as shown in Fig. 1.

By arranging the heater tubes in this offset relationship and using jump-over headers, a plurality of streams of `hydrocarbon fluid may be passed through a single row of tubes in the radiant heating section I2 and due to the arrangement the heater tubes are placed closer together than would be possible if standard headers and alined tubes were used. With the jumpover headers all on one side, narrower header boxes may be used and even though the header boxes are deeper because of the staggered tubes, the narrower header boxes are cheaper than header boxes previously used.

Streams A and B are substantially uniformly heated in their passage through the rows 38 and 48 of heater tubes in radiant heating section I2 and are heated to conversion temperature. The heated streams A and B are then passed through alternate heater tubes in double rows of heater tubes in the second radiant heating section I4 adapted to function as a soaking section wherein further radiant heat `is preferably supplied by burners or the like 24 and 26. Streams A and B pass through a horizontal row of exposed roof tubes generally designated 16, then through a vertical row of exposed side wall tubes generally designated 18, then through a vertical row of shielded side wall tubes generally designated 82 and then through a horizontal row of shielded roof tubes generally designated 84. The shielded wall tubes 82 are staggered with respect to the exposed row 18 and are positioned between the exposed row 18 and the side wall 85 of the heating apparatus. The shielded row of roof tubes 84 is preferably staggered with respect to the exposed row of heater tubes 16 and is positioned between the exposed row 16 and the roof 86 of the heating apparatus. During passage through these heater tubes the streams A and B are maintained separate and in parallel flow and are maintained at conversion temperature for the desired length of time to effect the desired extent of conversion.

Stream A of hydrocarbon fluid heated to conversion temperature and passing through line 18 is passed through first heater tube 81 in the exposed row of roof tubes 16 in radiant heating section I4 and then passes through jump-over header 88 to the third heater tube 88. In Fig. 1 the jump-over header 88 and other jump-over headers connecting certain of the heater tubes at one end of the heating apparatus have been omitted for purposes of clarity. These jumpover headers are shown in Figs. 5, 6 and '1 and will be more fully described hereinafter. The tubes connected by jump-over headers have their ends olset with respect to the ends of the remaining tubes similar to the arrangement shown in Fig. 2 as hereinbefore described. However, there are two rows of tubes in radiant heating section I4 and the arrangement will be more particularly described hereinafter.

From the heater tube 89 in row 16 the stream A passes through jump-over header 98 to heater tube 82. From this heater tube the stream A passes through jump-over header 83 and the stream A continues its passage through alternate tubes of the exposed roof tubes 16 and side Wall Cil tubes 18 and then through alternate tubes ofthe shielded side wall tubes 82 and finally through alternate heater tubes in the shielded row of roof tubes 84.

Stream B after being heated to Tconversion temperature in radiant heating section I2 and passing through line 12 is passed through second heater tube 98 adjacent rst heater tube 81 in the exposed row of roof tubes 16. Stream B is then passed through jump-over header 99 to an alternate tube |88 adjacent heater tube 8S hereinbeore described. Stream B then passes through jump-over header |82 to heater tube |84 adjacent heatertube 92 and then passes through jump-over header and passes through alternate tubes in the exposed row of roof tubes 13, alternate tubes in the exposed row of side wall tubes 18, and then through alternate tubes in the shielded side wall tubes 82 and then through alternate tubes in the shielded roof tubes 84. During passage through alternate tubes, streams A and'B are maintained separate.

More specically, stream A passes through alternate heater tubes in the rows of heater tubesl in the radiant heating section I4 as above described and through the following jump-over l headers in the order named, 98, 94 and |88 in row 16, jump-over headers ||8, |l2, ||4, and ||6 in row 18, and through header II8, then through jump-over headers |28 in the shielded side wall row 82 and then through headers |24, |26, |28 and |38 connecting alternate tubes in the shielded row or roof tubes 84. The above enumerated jump-over headers are the ones on one end only of the heatingapparatus but it is to be understood that there are similar headers at the other end of the heating apparatus, not shown in Fig. 1 but partly shown in Figs. 5, 6 and '1, to provide a continuous iiow for th stream A being heated.

The stream B passes through other alternate tubes or pairs of tubes in the rows of tubes in radiant heating section I4 and through jumpover headers |82 and |31 in` row 16, jump-over headers |32 in the exposed row of side wall tube 18, header |84 and then through jump-over headers |36 in vthe shielded row of side wall tubes 82 and then through jump-over headers |40, |4| and |42 through the shielded row of roof tubes 84. In connection with stream B only the jump-over headers on one side were enumerated as above explained in connection with stream A.

Before describing the arrangment of the heater tubes in the double rows of heater tubes, I will rst describe the passage of the streams A and B through the latter portion of the shielded roof tubes in row 84 before the streams A and B leave the heating apparatus.

Stream A after passing through the exposed rows of roof tubes and side wall tubes and shielded side wall tubes 82, is pass-ed through the shielded row of roof tubes 84 and the latter portion of this passage will now be described. Stream A after passing through jump-over header |43 (see Figs. 5, 6 and 7) is passed through heater tube |44 in row 84 then through jumpover header |38 to heater tube |46 andthen through jump-over header |41 to heater tube |48. The heated and converted stream A then leaves the heatingapparatus through line |58.

Stream B passes 4through jump-over header |l5| (see Figs. 5, 6 and 7), and heater tube |52 in row 84, then through jump-over header |62 to heater tube |56, then through jump-overheader |51 and iinally through heater tube U53. The heated and converted stream B is withdrawn from the heating apparatus through line |60.

While certain of the jump-over headers in Figs. 1 and '1 have been shown in different horizontal planes, it is to be understood that in the actual construction these jump-over headers for each row vof tubes have their horizontal portions in one plane as shown. in Fig, 6. Thehorizontal portions of the jump-over headers have been diagrammatic-ally shown in disal-inement in order to facilitate reading of the drawing.

Fig. 7 represents a diagrammatic showing of the flows of the streams A and B through certain of the tubes in the rows 4o-f roof -tubes 16 and 84, it being understood that the flows through the rest of the tubes in the two rows are similar. These tubes represent portions of the rows of tubes adjacent the roof 86 and. the convection heating section to show the flow of the streams A and B as they enter the radiant heating section I4 and as they leave the section t4. In Fig. '7 the jump-over headers shown in fulil lines are the jump-'over headers at one end of |the heating apparatus or furnace and the jump-over headers shown in dotted lines represent the jumpover headers at the opposite end of the furnace or heating apparatus.

Inspection of Figs. 6 and 7 will show that the jump-over headers in each row ail extend on one side of the heater tubes, that is, the jump-lover headers for the shielded row of rooi tubes 84 as 'sho-wn in Fig. 6 extend above `the row of tubes, whereas the jump-over headers in the exposed row of roof tubes 16 extend below the row of heater tubes. The headers for rows 118. and 82 also extend on opposite sides of the rows of heater tubes as sh-o-wn in .the drawing. With this construction the rows of heater tubes in the two rows adjacent the roof and side wall .of 'the radiant heating section I4 are arranged closer together and I am enabled to decrease the overall 'dimensions of the furnace and a considerable saving in construction cost is realized. By bringing the rows of tubes closer together, and with a :certain minimum allowlable distance from the center line .of the burners to the exposed row of tubes, there is a saving in space and the furnace may be made smaller. With the jump-over headers arranged according to my invention and using double rows of tubes, narrower and hence cheaper header boxes may be used.

In the double rows of heater tubes shown in radiant heating section I4, alternate tubes in each row are .offset as described in connection with Flig. 2 .of the single row of heater tubes and in this way jump-over headers connecting alternate tubes are displaced with respect to adjacent jump-over headers. In Fig. a top plan View is shown having parts broken away to facilitate the disclosure. In this View heater tubes in both rows of roof tubes are included but the arrangement in each row is substantially the same as that `described in connection with the single row of tubes shown in Figs. l and 2. It is to be noted that the heater tubes shown in Figs. 5, 6 and 7 represent tubes in the rows of roof tubes 16 and 84, the lower row of roof tubes shown in these figures are the ones through which the heated hydrocarbon fluid rst passes when entering radiant heating Zone or section I4 and the heater tubes in the upper row representing those tubes through which the heated and converted streams of oil or hydrocarbon fluid pass before leaving the heating apparatus.

Referring to Figs. 5 and 7, .the stream A passes through the heater tube 81, jump-over header 88, heater tube 89, jump-'over header 9i), heater tube 92, jump-over header S3, etc., through the remaining tube-s until the latter portion of the shielded row of roof tube 84 when the heated stream A passes through jump-over header |43, heater tube |44, jump-over header |30, heater Itube |416, jump-over header |141, heater tube |48, and then leaves the heating Iapparatus through line |56. Stream B follows a similar path which will be evident from an inspection of the drawing and the description of the ow of stream A just given. After being heated and converted the streams A and B ieaving radiant heating section t4 through lines |50 and i60, respectively, may be `combined and passed to apparatus to separate a desired motor fuel containing gaso- `line constituents, or the streams may be separately treated.

While I have shown one Iiow of the streams A and B through the radiant heating section iii it is to be understood that modicationls of this flow maybe used. For example, the streams A and B instead of being passed through the exposed row of roof tubes 16 and exposed row oi side wall tubes 18 in radiant heating section Ii may be rst passed through shielded row of roof tubes 8i and then through shielded row of side w-all tubes 82 and then through the exposed row of side wali tubes 18 and finally through the exposed row of roof tubes 16.

My invention is primarily adapted for use in heating plural streams of the same hydrocarbon fluid to conversion :temperature so that large volumes of hydrocarbon :duid may be uniformly heated, but plural streams of hydrocarbon uid having different characteristics may be heated in tubes arranged in offset relationship and connected by jump-over headers, if desired.

While I have shown a specific form of my invention it is to be understood that this is by way of example only and that vari-ous forms and modincations may be made without departing from the spirit of my invention.

IY claim:

.1. In a heating apparatus vadapted for heating hydrocarbon uids and having :a heating section, a row of heater tubes therein, alternate heater tubes in said row being olset with respect to the remaining heater tubes in said row so that the ends of alternate tubes are offset with respect to the ends of the remaining heater tubes and jump-'over headers disposed in planes transverse of the tubes and connect-ing the ends of alternate tubes with adjacent jump-over headers connecting alternate pairs of tubes being disposed in different planes, said jump-over headers being all arranged on one side of said row of heater tubes.

2. In a heating apparatus having a heating section, `a row of heater tubes arranged adjacent a boundary surface thereof, alternate heater tubes being offset with respect to the remaining heater tubes so :that the ends of alternate tubes yare in the same plane but offset with respect to the ends of the remaining heater tubes and jump` over headers connecting the ends of alternate tubes, said jump-over headers extending at substantially right angles .to the plan-e of said row of heater tubes and being ali arranged on one side of said row of heater tubes, adjacent jumpand connecting alternate tubes, adjacent j-umpover headers connecting alternate pairs of heater tubes being disposed in parallel planes.

4. `ln a heating apparatus having a heating section, a row of heater tubes arranged adjacent a .boundary surface thereof and adapted to conduct iluid therethrough, alternate heater tubes having their ends offset with respect to the ends of the remaining heater tubes so that the ends of alternate tubes are in the sam-e plane and the ends of adjacent tubes are in diiierent planes,

and headers ldisposed in planes` transverse of the tubes and connecting alternate heater tubes with adjacent hea-ders connecting alternate pairs of tubes being disposed in diierent planes, whereby the heater tubes are relatively lclose to eachother and a plurality of separate streams of fluid may be passed through alternate tubes and heated simultaneously an-d uniformly in passing therethrough.

5. In a heating apparatus having a heating seccion, double rows `of heater tubes therein, alternate heater tubes in each row being offset with respect to the remaining heater tubes in e-ach respective row so that the ends of alternate tubes in each row are offset with respect to the ends of the remaining heater tubes in each respective row and headers for each row dispose-d in planes transverse of .the tubes and connecting alternate heater tubes in each respective row, with adjacent jump-over headers connecting alternate pairs of tubes being ldisposed in different planes and the headers associated with one row of heater tubes vextending on one side of said row and the headers associated with said other row of heater tubes extending from the opposite side thereof.

6. .In a heating apparatus having a. heating section, double rows of heater tubes arranged adjacent boundary surfaces thereof, alternate heater tubes in each row being offset with respect to the remaining heater tubes in each respective row so that the ends of alternate tubes in each row are .offset with respect to the ends of the remaining heater tubes in each respective row and jump-over headers for each row di-sposed in planes transverse of the tubes and connecting alternate heater tubes in each respective row, adjacent hea-ders in each row connecting alternate heater tubes being disposed in parallel planes, said headers for one row extending substantially at right angles thereto and being positioned on one side oi. the plane ,of said row of heater tubes and said headers for said other rour extending substantially at right angl-es thereto and projecting in a direction away from said rst mentioned row of heater tubes, whereby said heater tubes .are arranged relatively closely together and a plurality of streams of fluid may be uniformly heated.

,7. A heating apparatus adapted to heat plural streams of hydrocarbon iiuid to conversion temperature, including two radiant heating sections, a single row of heater tubes in one heating section and a double row of heater tubes in said second heating section, alternate heater tubes in each row being offset with respect to adjacent heater .tubes so that the ends of alternate heater tubes are offset with respect to adjacent heater tubes, jump-over headers disposed in planes transverse of the tubes and connecting alternate heater tubes, adjacent headers connecting alternate pairs of heater tubes being parallel, means for supplying radiant heat to said radiant heating sections, to thereby provide for the passage of plural streams through alternate tubes in said single row of heater tubes in one radiant heating section thence through alternate tubes in one of the rows in said double row in said second nadiant heating section and finally through alternate tubes in the other row in said double row of heater tubes.

8. In a heating apparatus having a heating section, a plurality of rows of heater tubes arranged adjacent .a boundary surface thereof, said heater tubes in said rows being arranged in staggered relation, each row having alternate heater :tubes offset with respect to the remaining heater tubes in sai-d row so that the ends of alternate tubes are in the same plane but offset with respect to the ends of the remaining heater tubes in said row and headers disposed in planes transverse of the tubes and connecting alternate heater tubes, adjacent headers in each row and connecting pairs .of alternate tubes being in different planes whereby the heater tubes in said row are relatively close together and plural streams of hydrocarbon fluid may be passed through alternate tubes.

J OHN HERMAN RICKELRMAN. 

